What is Walking Accessibility?

To help us gain a deeper understanding of how efficient a public transport network is, we have chosen a set of indicators that our research has shown to describe the Supply side of Public Transport (PT).

Walking accessibility is one of these indicators and is used to measure how easy it is to access public transport within a specific walking time. Generally, the higher the number of stops, the more accessible PT is by walking.

How do we assess Walking Accessibility?

With Insights, we currently use a walking time of 5 minutes, a time frame that people are willing to walk to public transport stops. This equates to a walking distance of approximately 400m, using an average walking speed of 5.0 km/h. We calculate how far we can get in 5 minutes from any given location and then count the stations within that radius.

We repeat this calculation every 500m, until the whole region of interest is covered. A 500m interval is enough to have a precise estimate of the Walking Accessibility of an area. Measurements can be specified for any distance interval.

What data do we use?

To find the nearby stops, we need to know their locations. If the PT agency provides us with a GTFS file, we are able to use coordinates from that. If the GTFS data is not available, we can use OpenStreetMap data as a good second option to detect the locations of these stops.

Keep in mind…

It is possible for PT stops to reside inside the cell we are analysing and still not be reachable within a 5-minute walk. These stops are not taken into account in the Walking Accessibility score calculation for this cell.

Conversely, it is possible for stops to reside outside of the cell and still be reachable within a 5 minute walk. These stops will be included in the Walking Accessibility score calculation.

If there are no PT stops that can be reached within a 5 minute walk, the lowest score is assigned to the cell. The highest score will be assigned to cells with 5 or more stops.

This blog post is part of a series of articles that looks at how door2door’s Insights application evaluates Public Transport.